Clutch



Feb. 28, 1933.

G. F. THOMAS ET AL CLUTCH 4 Sheets-Sheet 1 Filed Feb. 18, 1950 Feb. 28, 1933. G. F, THOMAS ET AL 1,899,834

CLUTCH Filed Feb. 18, 1950 4 Sheets-Sheet 2 Feb. 28, 1933. G. E THOMAS ET AL 1,899,884

CLUTCH l Filed Feb. 18, 1930 4SheetS-Sheet 4 57 6@ 765737Z f/ /Z 6 /7 Z/ Y! T1 V Patented Feb. 28, 1933 UNITED STATES PATENT oFFicEj C, GEORGE FREDERICK THOMAS, OF CAMBERWELL, VICTORIA, AND THOMAS IOUNCAN i LEAPER, OF ST. KILDA, VICTORIA, AUSTRALIA 3 CLUTCH Application IedFebIuary 18, 1,930, Serial No. 429,353,and in Australia April-2, 1929.

" toco-act with the driving and driven members of the device and, under certain conditions, provide a driving connection which allows the driven member to overrun the driving member.

One of the objects of the present invention is to provide improved controlling means for the .frictional gripping elements of an overruiming clutch or like device, the controlling means being readily operable to posif tionV the gripping elements for transmitting the drive from the driving to the driven member of 'the device. This is effected by `the Vprovision of means adapt-ed to engage the gripping elements to cause them to roll into positions for driving.

The improved means also provide for the grippingelements being automatically caused to revert to driving positions when the speed of the driven member reverts to synchronism with the speed of the driving member after the driven member has been caused or allowed to overrun. The gripping elements can of course be setin a neutral position sothat clutching will not take' place in either direction. v

It is to be understood that the foregoing objects may be obtained if and when the driving member becomes the driven member and vice versa.

A clutch embodying the present improvements is particularly suitable for use as a so called free wheel or coasting device for automobiles and in such adaptation is fitted between the gear box or change speed mechanism and the propeller or Cardan shaft. But inl order that this invention may be readily understood reference will now be made to the accompanying drawings wherein certain constructional forms of the invention are illustrated by way of example. In these drawings, Y

Figure 1 is a sectional elevation of a clutch embodying improvements in accordance with `this invention. The section is taken on the line I-I of Figure 2.

Figure 2 is a fragmentary `cross section taken on the line II'-II ofFigure `1.

Figure 3, is a view showing two of the frictional Y.gripping elements with associated parts, taken approximately on fthe liney III-III inFigure 1. 5 Figure is similar to Figure 3 but showing the parts in another position.

Figure is` similar to Figures 3 and 4,

but :shows the parts in yet `another position. Figure 6 is an enlarged view of some of the parts seen in Figures 1, to. y y Y Figure 7 is a fragmentary cross section wherein gripping elements are shown in posil i 65 tions corresponding toFigure4. v

Figure 8 is a fragmentary cross section wherein gripping elements are shown in positionscorrespondin toFigure 5.- Figure 9 isa ragmentary section of a clutch showing a modified form of controlling means. 4' Y Fi ure 10 is a section taken on theV line X-v of Figure 9. l

Figure 11 is a sectional line XI-XI of Figure 9.

` Figure 12 is a fragmentarysection of another` modied form of controlling means.

vFigure 13 is an elevation of aconvenient form of operating means for a clutch embodying the present improvements for application to an automobile. y y

Figure 14 is a sectional ,elevation` of a clutch embodying another constructional form of the present invention, the section being taken approximately on the line XIV-XIV in Figure 15.

Figure 15 is a fragmentary cross section taken approximately on the line4 XV-XV in Figure 14. 1

Figure 16 is a fragmentary section takenA approximately on the line XVI- XVI in Figure 15. Y

Figure 17 is an inverted plan view taken plan takenon the yapproximately on the lineXVII--XVII in Figure 16.

Figure 18 is a detail in side elevation of a member of the control means-seen in Figure 14.

Figure 19 is a part sectional plan of the member seen in Figure 18.

Figure 16.

Figure 2O is an enlarged perspective of a clearly seeen in Figure 6 each slot 22 may member of the control means seen in Figures have an inner portion 23 which is relatively wide and an outer portion 24 wihch is rela- 16 and 17.

Figure 21 is a fragmentary section taken tively narrow, the portions 23, 24 being conapproxiinately on the line XXI-XXI in nected by a tapering portion with inclined i edges 26. Centrally of the width of portion Figures 22 to 25v are like fragmentary sec-l 23 and projecting therein is a detent 27 havtional views showing certain members of the ing a bevelled Outer and 28 The Outer end @Outrellng I rleauSk irl different OSOHS- of the lug 21 may be similarly bevelled and Figures 26, 27 and 2S are I'agmenily it may have anoseor extension 29 Lcapable views showing other members of the oonof lying fiat against the side faces ofthe 'trolling means in corresponding different "datent 27, positions. Y r Y Each slide 18 may be yieldingly urged into Figures 29 30er@ 31 are Plar1 VeWS taken or retained in .the position shown inFigure 1 pplOXHltely 011 lines XXIX, XXX, by a spring 30 in the respective'bore 19 and XXXI 0f Figures 26 27.' aud 28 respectively the slides may be moved in unison against the Figure 32 ShOWS*eeuyeueut'eperatlve 00uin'lu'ence of the springsby means of a control vueeterle extending between a eluteh deVee ,ring 31 which encircles the driving member 2 ae uuetrateetm Fgureeilt tegel land a Pedal and has pins 32 passing through slots33 in theY s ofk a conventional clutch as provided on an Outer part of them-ving membenthe pnserb eetemeible f between the engine' end the gagingthesiide i8. 'rhewidth'ofthe-controi Change Speed meebamemring may be such that it completely covers the In the dra-Wlrlge the numerate 2 and 3 slots 33 at all positionsV of the ring. f derletereepeetyely Outer and meer members In operation, assuming the slides 18 to be et, a free Wheel 0r Overrurmmg I eluteb- Vin the positionshown in Figures 1 and 3 and Eltber er these members may I aet ae tbe the driving member 2 to be rotating in the didryeu member: but rer the Purpose et tble rection indicated by the arrows A in Figures 2 y description it will be assumed that the outer amig, than' the gripping elements 4Vwill take yments 4.

membera is the, dryer- Fretebal grrPPmg up the position1 clearly illustrated inrFigure elemente 47 Shown m tbe'rerm et rollers are 2 which will result in the driven member3 Smtably retamed m ereumrerebtlauy ePaee rotating in the same direction as thejdriving relatleushlp m a Cage 6 and adapted te en member. The cage 6 is urged in the reverse gage Cam Surfaces 7 formed m the 1Imer direction to the arrows A by the springsv 30 periphery et thedrVmg member 2 Bear forcing the fbevelled ends vof the lugs 21k mge 8 Wbeb may 1r deslred be O r the thrust against the complementary bevelled ends of type may bepreylded temamtam tbe mem' the detents/27. It will be seen thereforethat bere 2 aud m Proper amar abgbmerltj ,O be in this condition the device vprovides Va cou- Or tbe bearmge 8 may be retamed m Peel/tum pling between the'members 2 and 3 with abiliby a eeyer Plate 11 surtably attached t0 tbe ty for the driven member 3 to overrun, and for coupling to be again established when r driving member 2. v

Extenamgwaroubd the Inner Pemphery et thespeed of the driving member 2 synchrothe drlymg member aand Preferablyabeut nizes with that of the driven member. It mdway er lts Wrath 1S agree@ la aeeem should also be noted that the extensions 29 of medatmg a number er Presser'members 13 the lugs 21 counteract any tendency of ther which .may be retameetm ereumferentlauy detents 27 to override due to any thrust imspaced relationship by spacers 14 .(Figure 2). parted .by the gripping elements when free The Presser membera are Shown ,m tbe ferm wheeling, the noses 29 and the side faces of of steel or metal strips Lcurved complemen'- the detents providing positive Stop f tary to the inner periphery of the driving tact With Say a Parr er tbe grllebmg tele' the strikers 17 engage the ribs 16 on the press- .v er members 13 while the driven member is Eaeh Presser rmay have 3- ClrCulufer-@Dtll overrunning the driving member 2, the pressrlb 15 Preleetmg rremlte Outer er eemeX ers will be depressed against the gripping ele- Surraee rer etrebgtbebmg PurPeeee and also. ments 4 which are thus caused to roll about to provide an. abutment Iadapted lto be .QII- their ownaXes in the direction of the arrows, gaged by a Strlker 17 (m a Sbde ,18 t0 thereby Figure 7 until they arrive at and engage the s On moving the control ring 31 to the'right member, eaebbreeeerrbeme' adapted te een' from the position shown in Figure 1 until` force the respective'presser into contact with Opposite end portions of the @am Surfaces 7 i its associated gripping elements. The slides as indicated@ Figure 7a S0 that on 'release 0f 18 may be housed in bores or keyhole slots 19 the Control fing it will return to the left and in the outer part of the driving member 2,.`the bevelled end of each lug Q1 will be disand each Slide 'may be provided at its fOr-"fiposed at the opposite side of the bevelled end ward end with an inwardly .projecting lug 21 adapted to engage a Vslotor recess 22 in of the detent 27, as indicated in Figure 4,; l l thereby causing the cage to be urged under the outer surface of the cage 6. As more influence of the springs 30,lugs 21 and detents @its 27 in the direction of the arrow A, Figure 2. In this condition the member 2 can be considered as a braking member to the member 3 and can also be used as a driving member in` the direction of the arrow B, Figure 2. Assuming now that the control ringv 31 be moved to the right for the full extent of its movement while the driven member 3 isoverrunning or while driving isenot being effected, then the strikers 17 will have passed over 'the ribs 16 depressing the pressers 13 and thus allowing the gripping elements to be freed from the positions shown in vFigure 2, and each lug 21 will be directed by the inclined edges 26 of its slot 22 into the central relatively narrow portions 24, as indicated in Figure 5, with the result that a condition of unconpling exists between the driving and driven members, the gripping elements 4 being disposed about midway of the length of the cam surfaces 7 as in Figure 8.

Referring now to Figures 9, 10 and 11 which illustrate a modified construction of spring influenced means to yieldingly hold the cag 6 at opposite sides of its neutral position, the detent 27 consists of a forward projection of a plunger 36 which is urged towards the lug 21 by a spring 37. The plunger, and the spring may be disposed within a metal block or carrier 38 having a slot with portions 23 and 24 and faces 26 the equivalent of those illustrated in Figures 1 and 3 to 6.

Y Figure 12 illustrates another modification of the spring influenced cage positioning means in which ball detents 39 urged outwardly from axial holes 41 in the cage 6 by springs 42 engage recesses or dimples in the inner surfaces of the driving member 2 and `the cover plate 11. The slides 18, strikers 17,

slots 22 in the cage, and the other associated parts are similar to those illustrated in Figures 1 to 6. Y

A convenient means for operating the device when applied to an automobile is indicated in Figure 13 and comprises a cam 46 pivoted at 46 to any convenient support and coupled to the usual engine clutch'pedal (not shown) by means of the rod 51. The cam has a slot having curved portions 47', 47" and 47 concentric with the pivot 46 but of different radii and receiving a pin 48 carried by a forked lever 49 pivoted at 49 and having a slipper block 49 on each of its arms adapted to engage the control ring 31. `Depression of the engine clutch pedal causes the cam 46 to swing on its pivot 46Kand the pin 48 to traverse the cam,` slot, the pin 48 being in the portion 47 when the engine clutch is fully engaged, in the portion 47 when the engine clutch is fully released and in the portion 47 when the engine clutch is in an intermediate position. During the time that the pin 48 is in the portion 47 the an automobile it is clear that at all times when 70 the engine clutch pedal is fully depressed the change speed mechanism is uncoupled at both ends, that is to say, by the usual clutch at the forward end and by the lugs 21 engaging the narrow portions 24 of theslots 22as in '75 Figure 5, the pin 48 being in'the cam slot portion 47 at this stage, .so that the gear changing operations are simplified. Should the automobile be stationary and it is desired to move off either in a forward or reverse direction the clutch pedal canv be fully depressed and the desired gear engaged; As

the clutch pedal is released and before final l engagement (that is, `when. thel pin 48 is yin the cam .slot portion 47 the movement of '85 the driving member 2 carrying .the pressers 13 which are still depressed, causes .the gripping elements 4 to roll to the correct end portions of the cam surfaces 7. It should be here noted that there is a slight lost motion 199 and overlap in the operation .of the .slotted cam 46 to ensure that Y `j (a) The pressers 13 are heldfdepressed until the driving member 2 has made. initialy movement during the time the pin 48 is in cam "95 slot portion 47. y

(b) Continued movement brings the lugs 21 and'their detents 27 into engagement so that the cage holds the gripping elements ready to re-engage Should the automobile be overrunning i. e. free wheeling andv it is desiredto use the engine as a brake an initial depression and release of the clutch pedal will cause the rollers and cage to be positioned as indicatedV in ill-'05 Figures 4 and 7. To again take up driving, a similar operation will be necessary. In order to'prevent shock in taking up the drive, the rod 51 will preferably be so adjusted that the usual clutch is partially engaged before the-Uo pressers 13 engage the gripping elements 4 to position them for braking. v 1

According to the embodiment illustrated in Figures 14 to 31 the presser members 13 are not depressed during the movement off-115 the control ring 31 from a clutching position to the neutral position butA are 4depressed dvring the return movement of the ring to thereby cause the gripping elements 4 to roll to the appropriate end poritions ofvtheir cam-13.120

surfaces 7. In this embodiment the slides movable with the control ring to actuate the pressers 13 are in the form of blocks 56 (see particularly Figures 18 and 19) accommodated by longitudinal slots 57 in the iii-7125 ner periphery' of the control ring. Each block may have at one end a substantially cylindrical portion 58 with a fiat face or square corner portion 59 extending transversely and.

adapted to contact with the outer 4face 61 ofi-130 after V overrunning. 1190 l the control ring except when the movement of the control ring, whilst each co-operating de-V the block is opposed as hereinafter referred to. Intermediately of its length each block has a slot 65 to accommodate the reduced head 66 of the pin 67 slidable radially within a radial hole 68 leading from a circumferential groove 12 in the inner periphery ofthe driving member 2. The inner end of the pin Iengages a stud 71 proj ectingoutwardly from the rear or convex surface of a presser member 13 into the radial hole 68. The outward movement of the pin 67 in hole 68 may be limited by a snap ring 72. The end of the kslot 65 in each sli-ding block remote from the cylindrical portion 58 is undercut or in other words reduced in height by a transverse shoulder portion 73 of less height than the cylindrical portion. rlhe under face 74 of the shoulder portion is adapted to engage the top ofthe pin head 66, and the outer face 76 of the shoulder portion is bevelled. The operation of the sliding blocks and associated parts will be described later.

In this embodiment instead of providing slots 22 in the outer periphery of the cage 6 as in Figures 1 to 8 similar slots 22, 23, 24, 26 are formed in the inner periphery of tent 27 consists of astrip of metal projecting intothe slot and held in position by an integral dovetail portion 77 which fits into a dovetail groove 78 ina side flange of the control ring. The lug 21 co-acting with the slot v22" and detent 27 instead of being movable with the control ring as in Figures 1 to 12'is attached to the cage 6 and as clearly seen in Figures 15 and 16 may consist of a flattened head of a pin 79 which passes freely through a circumferentially elongated passage 81 in the driving member 2 and into a radial hole 82 in the cage to which it may be retained by a screw 83. In order to urge the cage in opposite directions according to different positions of the mechanism, the driv- -ing member 2 may have a number of boresA 84 (Figures 16 and 21) with reduced inner ends through each of which a ball 86 is pressed by a spring 87. The balls are adapted to engage the pins 79 at one side of their longitudinal centres when the pins are in their extreme positions, that is when they are not aligned with the central narrow part 24 of their slots 22. It will thus beevident that the spring pressed balls 86 by acting on the pins 79 tend to urge the cage 6 in the direction which will depend on the position of the pins 79 in the circumferentially elongated passages 8l of the driving member.

When the parts are in the positions'indicated in Figures `14, 15, 16, 17, 22, 26, and 29 the device provides acoupling betweeny the driving and driven members which lallows the driven member to overrun. It will be noted from Figures 14 and 22 that the sliding f member is rotating at high speed they may be projected outwardly of the yholes 68 by centrifugal force, the snap rings 72 limiting the outward movements of the pins asbeforementioned. n

On moving the control ring 31 tothe right from the position shown inliliguresllY and 22 it will carry each sliding block 56 with it until one end of theslot 65 in the sliding block contacts with the pin head 66 as seen in Figure 23, thereupon kthe motion of the sliding block will be arrested. `It will also be seen that the shoulder 73 of the block is clear of the Ypin head 66 so that during further movement of the control ring to the right a striker 17 carried by the control ring will ride over the shoulder 73I depressing same e position of the ring, the cage positioning'v pins 79 and lugs 21" will be in neutral positions as indicated in Figures 28 and 31.

On return movement of the control ring from the position shown in Figure 24 the sliding bloclr 56 is carried therewith until its shoulder 73 is brought above thehead 66 of the pin 67 as in Figure 25 and the shoulder portion of the block is raised or tilted. It will be clear thatby continuing the return` movement of the control ring, the striker 17 ywill engage and ride over the shoulder 73 depressing same and thus moving the pin 67 inwards so that the pressers 13 will bey engaged with the gripping elements 4 ready to cause them to roll tothe driving position as governed by the differential speeds of the driving and driven members 2 and 3.

If the driven member happened to be overrunning the' driving member the gripping' elements4 would be rolled into positions indicated in Figure 15. To ensure that the control ring has purely longitudinal movements it may be provided with one or morelongitudinal slots (Figure 15) to accommodate guide pins or studs secured to and outstanding from the driving member 2.

The tip of each detent 27 may be bevelled as seen in Figures 17, 29, 30 and31 in order to deflect lug 21 intoposition for normal driving when the driving and driven members have no relative motion.

The action of the device illustrated in Figures 14 to 31 is similar to that illustrated in the previous figures with the exception that Vers 94 co-operating the pressers 13 are depressed only. when the control ring is moving from a declutching position into a clutching position. y

. Any suitable means may of course be provided for operating the control ring 31 and we have shown, by way of eXample, a suitable operating m-eans in Figure V32 wherein the usual clutch pedal 8'8 of an automobile is connected by a rod 89 and a dead eye l9() with. an intermediately` pivoted forked leverl 91 carrying slippers 92 for engaging the'control ring 31 between its side flanges. 4The rear end portion89a of the rodmay be screwV the engine to act as a' brake and the main clutch is thrown out, the device will continue to actuate the gears and the likeof the change speed mechanism and the gripping elements 4 will be under a slight load. In such conditions depression of the clutch pedalmay place a strain on the cage positioning pins 7 9 if the load on the gripping elements is suflicient to resist the neutralizing action. To avoid damage to the pins 79 Vthe spring 95 is placed under sufficient compression to ensure normal operation under ordinary conditions but to yield in order to relieve the p ins 7 9 of strain when the deviceis in tliecondition previously mentioned.

If it is desir-ed, provision may be made whereby the driving and driven members may be directly connected or locked together at the will of the driver or operator so that in the event of any breakage or defect in themechanisni or for any other cause or reason, a direct drive may be obtained. For this purpose the hug portion or shaft 98 of the driven member may have a dog clutch niember 99 slidable axially thereon by means of suitable operating gear into engagement with a clutch face 101 on the cover plate 11 as indicated in Figure 32.

In all cases it should be understood that the device can be disposed within a casing 97 (Figure 32) charged with oil or grease,

and that the driving and driven members 2 and 3 may be adapted in any suitable manner for connection to shafts or other parts. It should also be understood that devices embodying the invention are not limited in their application toautomobiles but may be aplied with advantage to machines of many different kinds. y

Having now described our invention what we claim as new and desire to secure by Letters Patent is z- 1. In a clutch or like device a :driving inember, a driven member, said members having with the deadeye 90 .concentrically spaced circular surfaces, one surface being plain; and the other provided with cam faces which are spaced apartand elongated.circumferentially, rollers disposed between the cam faces and the plain circular race, and control means including a presser member operable to presstlie rollers against the plain falceA and having a surface which "cooperates with the plain face to therebyfoi'm between them a pathalong which the rollers `are, rolled by friction with said. face into different positions circumferentially of ysaid cam faces according to differential speed .off

rotationof the driving and driven members.

concentrically spaced circular surfaces, one of said surfaces being plain and the otheri provided with circumferentially spacedhcam faces, acage disposed between said concentric y .spaced surfaces andcapable of relative ,cir. 1 rcumferential movement, `rollers `carried by said cage and adapted to contact with said cam faces and said plain surface, means: engageable with saidl rollers to cause them to roll into different positions between saiddrivurging the cage under certain conditions ina direction tending to maintain the rollers'in drive transmitting contact with the cam faces `and plain circular face.

the other ,providedfwith circumferentially y A2. Inaclutchor-like device,aldrivingmemf ber, a driven member, said members having ing and driven members, Aand resilient ymeans y Y ioov spaced cam faces, a cage dispose-d between said circular surfaces and capable vof relative Vcircumferential movement, gripping elements lsuch as rollers revolvable in said cage and capable of contacting with said camsurfaces and the opposing plain circular face, means adapted to press said gripping elements p against said plain complementary faceso that they may be'causedto rollcircumferentially of said cam surfaces due to differential speed of 'rotation of the driving and driven members, and resilient means urging said cage under certain conditions in a direction tending to maintain the gripping elements in `driveV transmitting positions `irrespective of which meinberis, for the time being, acting as the driving member. 'v

4. A clutch in accordance with. claim 8 and further characterized in' that said cage with said gripping elements is movablev into three different positions relative to said cam faces,

in oneposition the gripping elementsenabling member, in another position-,causing the driving member to act as a `brake preventing excessive speed of `rotation of the; driven member, and in the'third position allowing independent rotation of `the members, the

the driven member toover-run the 'driving l when the-gripping elements are inthe first mentioned' position, tending to move the cage 'inthe'V samedirection as the driving member when the gripping elements are in the seco nd position and holding the cage fixed to `the driving vmember when the ments'are in the third position.

5`- A clutch in accordance with claim 2 and lfurther characterized by a single control gripping elemember adapted to actuate said roller en- `ga-ging means and also to set said means jactin'g on said cage in positions correspond- Ving to those of the rollers.

6i In a clutch or like device a driving member, a driven member, said members having lco'ncentrically spaced circular surfaces, one Vsurface being plain andtheother provided 'withcam faces which are spaced apart and elongated circumferentially, rollers disposed between the cam faces and the plain circular face, one or more presser elementsk movablycarried by the member having the i cam faces,` and operating means whereby the presser elements' may press the rollers against the plain circular face to cause the rollers 'to vary their positions with regard to the camfaces according to differential speed of rotation of said driving and driven members said presser element operating means com- 'prising a 'control member slida-ble on one of said members and provided with strikers adapted to engage said .presser elements.

7.A Ina clutch o-r like device," a driving A'neeeali vprojecting overtli'e slot ofeacli block toengagel theV respective pin.

9. A clutch or like device' comprising driving and driven members providing outer yand inner surfaces between which-frictional ,tripping elements are disposed, vand independent control elements providing a further surface cooperating with a surface of one of said members and thereby forming a `path along which the frictional gripping` elements are caused to travel in-taking up a driving position due to differential speedof lsaid driving and driven members. Y

' 10. A clutch or like device according to claim l and in which the presser member is rmovably carried by the member having the cam face.

In testimony whereof we affix our signatures. f

y GEORGE FREDERICK THOMAS. THOMAS DUNCAN LEAPEE.

member,a driven member, said members having concentrically spaced circular surfaces one of which is plain and the other provided 'with circumferentially spaced cam faces, a Ycage disposed between said circular surfaces and capable of relative circumferential move- Yment, rollers carried by the cage adapted to vvContact with said cam faces and saidV plain v tain said rollers in drive'transmitting contact withsaid cam faces and said plain circular face, and means operable by, and duri ing movement in each direction of, said con- Ytrol member, for setting said means acting on the cage in positions correspondingy to those of said rollers.

8.v A clutch in accordance with claim 7 and further characterized by said control member being in the vform of a ring slidable axiali lly around the clutch, and provided with longitudinal grooves `in its inner periphery,

`slotted blockslocated one ineach of said grooves'capable vof moving with said ring and also tilting within said grooves, presser 1 members for engaging the rollers, operating `pins for said presser members projecting into the slots of said` blocks, and a shoulder'- lOO 

